Magnetic switch



Oct. 28, 1941. D. BucclcoNE ETAL 2,260,771

MAGNETIC SWITCH Filed Sept.` '7, 1959 F|E.1 f EIS?. Fusi.

Patented oet. 28, 1941 UNITED STAT Es PATENT OFFICE MAGNETIC SWITCH Dario Buccicone and Charles M. Shank, Gary, Ind.

application september '1, 1939, serial No. 293,854

(c1. 2x5-9s) 6 Claims.

. articles and a counter adapted to register the movement of articles fed by the conveyer.

The invention will be fully apparent from the following detail disclosure, when read in connection with the accompanying drawing and will be dened with particularity in the appended claims.

In the drawing:

Figure 1 is a longitudinal section through a switch actuator embodying theinvention;

l Figure 2 is a view at right angles with parts shown in section; 'l

Figure 3 is a section of a switch shown in Figure 1 adapted to be actuated by the device of the present invention;

Figure 4 is a section on line IV--IV of Figure 3; and

Figure 5 is a somewhat diagrammatic view showing the invention as embodied in combination with a conveyer and a counter for registering the number of articles fed by the conveyer.

Referring in detail to the drawing, the numeral I0 represents conventionally any suitable type of conveyer which may be regarded as either a belt or a night conveyer which travels over a plurality of guide sheaves l2. The conveyer illustrated is adapted to feed a succession of metal sheets S in the direction of the arrow X. The sheets or other metallic articles are fed at a high rate of speed by the conveyer and each article fed is registeredl by a counter I4 located at any convenient station.Y The counter is .of conventional form and has an operatingfinger I6 normally urged upwardly by a; spring" I8 against a fixed stop 20. Each time a sheet or other article on the conveyer passes the actuating device-22 of the present invention, a circuit is closed through a solenoid 24 or other electromagnetic device capable of imparting an impulse to the solenoid armature 26 which thus serves in coaction with the finger I6 as the counter actuator. The solenoid 24 is in circuit with a battery 28 and a movable switch element 30 adapted to coact with .a fixed contact 32. The switch element 30 may be of any' conventional form and its detailsform no part of the present invention. Preferably, it is a normally open switch; thus' every time the circuit is closed through the fixed contact 32, an

electrical impulse is imparted to the so1enoidv24' yof the core.

so as to register each of the articles successively Vfed past a given station.

An important feature of the present invention resides in the switch actuator mechanism, indicated generally at 22 and shown in detail in Figures 1 and 2. This actuator includes a continuously energized electromagnetic coil 34 located within a suitable yshell 36 having a suitable lug 38 by means of which the device can be mounted by screws 40 to any xed support. Extending axially o the coil there is a iixed magnetic core 42, the outer extremity 44 of which terminates in a plane below or short of the normal plane of travel of sheets or other metallic para-magnetic articles to be fed. The core is formed with an axial chamber or 'bore 46 Within which is slidably mounted a plunger 48 of nonmagnetic material having a shank 56, the lower end of which is guided by an axial opening formed in a bushing 52 screwedl in the core. A compression spring54 interposed between the bushing 52 and the lower end of the plunger 48 normally presses thev plunger upwardly to the positionv shown in Figures 1 and 2. Extending laterally through slots 58 formed in the core there is a small shaft 56 ,which carries rollers 60-60 of non-magnetic material disposed on opposite sides The slots 58 in the core 42 coact with the shaft 56 to guide the plunger 48 in its vertical movements and to maintain the rollers 60 inproper position to be actuated upon attraction of the sheets by the magnetic coil 34. 'I'he outer peripheries 62 of the rollers extend beyond the plane of the upper extremity 44 of the core and are substantially or approximately coincident with the normal plane of travel of the undersides of the articles fed by the conveyer or, if desired, the peripheries of the rollers can be spaced slightly below the plane of travel of the undersides of the articles.

The lowe'r` extremity of the shank 50 coacts with a switchoperating finger 64 which is pivoted at 66 to a suitable iixed supporting lug. A spring 68 normally holds the finger 64 in the position of Figures 1 and 3. In this position the free end of l the finger holds a push button 10 of a conventional switch in its upper position against the action of a spring 12. The push button vcarries a pin 14 which works through suitable slots in the button guide sleeve 13. Thus, it is clear that the finger 64 normally holds the push button 16 in such position that the finger 30 thereof is in open circuit condition with respect to the fixed contact 32. Thus, when the finger 64 is depressed by the shank 50, the spring 12, acting through the pin 14, will move the switch 30 from its normally open position to closed circuit position.

In operation, as the conveyer feeds the metal sheets in succession past a predetermined point, the field of magnetic flux set up between the continuously energized winding 34 and theupper extremity 44 of the core 42 will be concentrated through the pointed end of the core, as suggested by the dotted circles in Figure 2. The iiux lines of force iiow in a direction to attract paramagnetic articles such as the steel sheets S traveling on the conveyer in the plane above the electromagnetic coil 34 and the magnet core 42fex cited thereby. Thus, the sheets or other magnetic articles will be quickly attracted downwardly out of their normal path so as to force the plunger 48 downwardly against the action of the compression spring 54. The lower end of the shank 50 will depress the finger 64, rocking it about its pivot 66 against the action of the spring 68. The free end of the finger will then permit the push button to move downwardly under the action of the switch spring 12 and the pin 14 carried by the push button will press downwardly the switch contact 30, thus closing the circuit of the battery 28 through the solenoid'24 and causing an impulse to be transmitted to the counter.

From the foregoing, it is apparent that the invention provides a compact device comprising coacting instrumentalities eiective to exert a positive action on an electric switch by the-,use of a magnetic force. As each sheet Stravels along the conveyer, it is attracted toward the device. The magnetic attraction of each sheet causes the wheels 60 to depress the plunger 50 which is ei'- fective to close the switch contacts 30-32 which, in turn, causes an energization of the solenoid 24 which thus imparts an impulse to the counter. As soon as the sheet on the conveyer passes out of the influence of the magnetic force, the spring 4B quickly lifts the plunger, whereupon the circuit of the solenoid is broken and the parts are restored to starting position.-

Since, the instant that the trailing end of the sheet passes out of the influence o1 the magnetic field, the spring 54 comes into play to lift the plunger 50 and thus cause the circuit of the solenoid to be broken, it is apparent that a very small switch movement is required. This makes it possible to operate at a high speed, with a minimum space between sheets.

- Since the conveyer as above stated may be regarded as either a belt or a ilight conveyer, it is obvious that the rollers 50 may be depressed either by direct engagement with the underside oi' the sheets or by engagement with the underside of the belt when the sheets are carried by a belt conveyer. It will be understood by those skilled in the art that end portions of the'sheets may rest on conveyer chains of a ight conveyer and that in such cases intermediate portions of the sheets will be exposed on their undersides, f

except, of course, at those portions where the flights of the conveyer extend from side-chain to side-chain thereof.

While we have described quite specifically the embodiment of the invention herein illustrated, it is to be understood that various modifications may be made without departing from the scope of the invention, as defined in the following claims.

We claim: Y l

l. In combination, a conveyer adapted to prope1`magnetic articles, a counter adapted to indicate the number of articles fed by the conveyer past a given point, a switch, a iixed magnetic core adapted to attract each article in succession and deflect a portion of the conveyer as each article passes such point, a yieldingly positioned member slidable relative to said core adapted to be moved as the result of such attraction of a passing article, an article-engaging roller carried by said member, means responsive to the movement of said member for actuating said switch, and means controlled by said switch for actuating said counter. f

2. In combination, a conveyer adapted to propel magnetic articles, a counter adapted to indicate the number of articles fed by the conveyer past a given point, a switch, a fixed core, an electromagnetic. coil surrounding the core effective to cause it to attract such articles as they pass such given point, a plunger yieldingly positioned within a cavity in said core and guided by said core, an article-engaging roller located exteriorly of the core and operatively connected to said plunger for imparting movement thereto upon attraction of said articles by the core, means actuated by the plunger for operating said switch, and means controlled by the switch for operating the counter.

3. In combination, a conveyer adapted to propel magnetic articles, a switch, a fixed magnetic core having an axial chamber therein, a plunger in said chamber, a spring urging the plunger upwardly, a coil for magnetizing said core and eflfecfive to attract said magnetic articles downwardly as they are propelled thereover by the conveyer, article engagingvrollers exterior to the upper end of the core having a mechanical connection with said plunger and eiiective upon attraction of said articles to depress the plunger against the action of said spring, and means responsive to the movement of the plunger for actuating said switch, the said rollers being adapted to make a rolling contact with said articles as they are propelled by the conveyer past said coil.

4. In combination with a switch, a iixed core, having an axial chamber therein, a plunger in the chamber, a spring urging the plunger in one direction, a coil for magnetizing said core, said core having a transversely apertured portion, a shaft secured to the plunger and extending freely through said apertured portion', a sheet actuated roller carried by said shaft whereby said plunger is depressed against the action of said spring when said magnetic means attracts such sheet toward said core, said switch being normally in open circuit condition, and means for putting it in closed circuit condition upon movement imparted to said plunger by lthe action of a metal sheet as it is magnetically attracted toward said core and thus caused to actuate said roller.

5. The combination with a conveyer for feeding magnetic metal articles in succession and a counter for registering the number of articles fed,

Y of electrically actuated means for operating the counter, a switch controlling the circuit of the latter, a iixed magnetic core located in the line oi' travel of the articles as viewed in plan, and means for operating said switch, said means being movable relative to the magnetic core and arranged to be actuated when the latter attracts such an article in its travel past it.

6. The combination with a conveyer for feeds ing magnetic metal articles in succession and a counter for registering the number of articles fed, of electrically actuated means for operating the counter, a switch controlling the circuit of the latter, an electromagnet, one end of whose core terminates short of the plane of travel of the articles, a plunger slidably supported by the core and carrying an article-engaging roller,

means normally tending to position the periphery of the roller beyond said one end of the core, and means/'actuated upon movement of said plunger for actuating said switch whereby each time the conveyer feeds an article past said electromagnct DARIO BUCCICONE. CHARLES M. SHANK. 

